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111.
112.
Chen CC Fang CL Al-Suwayeh SA Leu YL Fang JY 《International journal of pharmaceutics》2011,415(1-2):119-128
The present work was carried out to design a practical, controlled-release transdermal system for selegiline using thermosensitive hydrogels. The copolymers of alginate and Pluronic F127 (PF127) were used to design thermogels by either physical blending (A+P) or chemical grafting (AP). The thermogels were characterized in terms of the sol-gel temperature, scanning electron microscopy (SEM), degradation ratio, and skin permeation behavior. The chemical grafting of alginate to PF127 could delay the sol-gel temperature from 24.1 to 30.4°C, which is near the temperature of the skin surface. The gelling temperature of the physical mixture of alginate and PF127 (A+P) did not significantly differ. The porosity of the A+P structure was greater compared to that of the AP structure. AP thermogels were regularly degraded, with 60% of the gel matrix remaining after a 48-h incubation. PF127 and A+P hydrogels showed almost no degradation. The results of skin permeation across porcine skin and nude mouse skin suggested that the thermogels could produce sustained selegiline release, with AP showing the most-sustained permeation. AP hydrogels exhibited linear permeation properties for the transdermal delivery of selegiline. Inter-subject variations in skin permeation were reduced by incorporation of the thermogel. Such a thermosensitive hydrogel can be advantageous as a topical therapeutic formulation for selegiline. 相似文献
113.
N.T. Wang H.I. Lin D.Y. Yeh T.Y. Chou C.F. Chen F.C. Leu D. Wang R.T. Hu 《Transplantation proceedings》2009,41(10):4110-4113
Objective
Ischemia/reperfusion (I/R) of the rat liver can induce liver injury through mechanisms involving oxidative and nitrosative stresses. In this study we examined the effects of antioxidants Lycium barbarum (LB) and ascorbic acid on I/R-induced liver injury in rats.Methods
Liver ischemia was induced by clamping the common hepatic artery and portal vein of rats for 40 minutes. Thereafter, flow was restored with reperfusion for 90 minutes. Blood samples collected before ischemia and after reperfusion were analyzed for alanine transaminase (ALT), lactic dehydrogenase (LDH), hydroxyl radical, and nitric oxide (NO) levels. Pharmacologic interventions included administration of ascorbic acid (100 mg/kg, i.p., 1 hour before I/R) or LB, an extract of Gogi berries: 600 mg in 100 mL of drinking water for 2 weeks prior to experimentation.Results
This protocol resulted in elevation of blood concentrations of NO, hydroxyl radical, ALT, and LDH (P < .001) in the I/R-induced liver injury group. Ascorbic acid significantly attenuated the reperfusion liver injury by attenuating hydroxyl radical (P < .01) and NO (P < .05) release. The LB aggravated I/R-induced liver injury by increasing hydroxyl radical release with no effect on NO release.Discussion and conclusions
This I/R protocol resulted in oxidative and nitrosative stress and liver injury. Ascorbic acid showed significant protective effects on reperfusion liver injury by attenuating hydroxyl radical and NO release. In contrast, LB aggravated liver injury by increasing hydroxyl radical release. 相似文献114.
E Bölke K Orth PA Gerber G Lammering R Mota M Peiper C Matuschek W Budach E Rusnak S Shaikh B Dogan HB Prisack H Bojar 《European journal of medical research》2009,14(8):359-363
Background
Breast cancer (BC) represents one of the leading causes of cancer related deaths worldwide. New tools for diagnostic staging and therapeutic monitoring are needed to improve individualized therapies and improve clinical outcome. The analyses of circulating tumour cells may provide important prognostic information in the clinical setting.Materials and methods
Circulating tumour cells (CTC) of 63 BC patients were isolated from peripheral blood (PB) through immunomagnetic separation. Subsequently, RT-PCR or mPCR for the genes ga733.2, muc-1, c-erbB2, mgb-1, spdef and c-erbB2 were performed. Subsequently, expression data were correlated with the tumour stages. Fourteen healthy individuals served as controls.Results
Significant correlations with tumour stages were found in single gene analyses of ga733.2, muc-1 and in multi-gene analyses of ga733.2/muc-1/mgb1/spdef. Furthermore, a significant correlation of Ca 15-3 and all studied genes was also observed.Conclusion
Herein, we demonstrated a positive correlation of a gene signature consisting of ga733.2, muc-1, mgb1 and spdef and advanced stages of BC. Moreover, all studied genes and gene patterns revealed a significant correlation with Ca 15-3 positive cases. 相似文献115.
116.
Invasive fungal infection in systemic lupus erythematosus: an analysis of 15 cases and a literature review 总被引:2,自引:0,他引:2
OBJECTIVE: To analyse 15 cases of invasive fungal infection and mortality parameters in the largest series in the last 35 yrs of patients with systemic lupus erythematosus (SLE) at a single medical centre. METHODS: Fifteen patients with SLE and invasive fungal infections were retrospectively enrolled. Clinical and laboratory data, fungal species and infected sites, corticosteroid and immunosuppressant doses and SLE disease activity index were assessed retrospectively. Comparison and correlation analyses utilized Fisher's exact test, the chi-square test, Mann-Whitney U-test or the Wilcoxon signed-rank test where appropriate. RESULTS: In contrast to other review reports, Cryptococcus neoformans was the most commonly identified fungus in this Taiwanese series. Notably, the prevalence of autoimmune haemolytic anaemia and positive results for the anti-cardiolipin antibody in this study were significantly higher than those in SLE patients in general (P < 0.0001 and P < 0.0001, respectively). Fungal infection contributed to cause of death in 7 of 15 (46.7%) patients, of which Cryptococcus neoformans accounted for six of these infections. Low-dose prednisolone (<1 or <0.5 mg/kg/day based on arbitrary division) prior to fungal infection tended to correlate with 1 yr mortality after diagnosis of SLE (P = 0.077 or P = 0.080). However, following fungal infection, patients who died from infection itself had been prescribed with higher prednisolone dose or equivalent than surviving patients (P = 0.016). All SLE patients with fungal infections had active SLE (SLEDAI >7). CONCLUSIONS: Cryptococcus neoformans infection accounted for most fatalities in SLE patients with fungal infections in this series. Active lupus disease is probably a risk factor for fungal infection in SLE patients. Notably, low prednisolone doses prior to fungal infection or high prednisolone doses following fungal infection tended to associate with or correlated to fatality, respectively. Therefore, we suggest that different prednisolone doses prescribed at various times impact the incidence of fungal infection and its associated mortality. 相似文献
117.
118.
119.
Schwindt CD Zaldivar F Wilson L Leu SY Wang-Rodriguez J Mills PJ Cooper DM 《British journal of sports medicine》2007,41(1):34-40
Background
Exercise can alter health in children in both beneficial (eg reduced long‐term risk of atherosclerosis) and adverse (eg exercise‐induced asthma) ways. The mechanisms linking exercise and health are not known, but may rest, partly, on the ability of exercise to increase circulating immune cells. Little is known about the effect of brief exercise, more reflective of naturally occurring patterns of physical activity in children, on immune cell responses.Objectives
To determine whether (1) a 6‐min bout of exercise can increase circulating inflammatory cells in healthy children and (2) the effect of brief exercise is greater in children with a history of asthma.Methods
Children with mild–moderate persistent asthma and age‐matched controls (n = 14 in each group, mean age 13.6 years) performed a 6‐min bout of cycle‐ergometer exercise. Spirometry was performed at baseline and after exercise. Blood was drawn before and after exercise, leucocytes were quantified and key lymphocyte cell surface markers were assessed by flow cytometry.Results
Exercise decreased spirometry only in children with asthma, but increased (p<0.001) most types of leucocytes (eg lymphocytes (controls, mean (SD) 1210 (208) cells/μl; children with asthma, 1119 (147) cells/μl) and eosinophils (controls, 104 (22) cells/μl; children with asthma, 88 (20) cells/μl)) to the same degree in both groups. Similarly, exercise increased T helper cells (controls, 248 (60) cells/μl; children with asthma, 232 (53) cells/μl) and most other lymphocyte subtypes tested. By contrast, although basophils (16 (5) cells/μl) and CD4+ CD45RO+ RA+ lymphocytes (19 (4) cells/μl) increased in controls, no increase in these cell types was found in children with asthma.Conclusions
Exercise increased many circulating inflammatory cells in both children with asthma and controls. Circulating inflammatory cells did increase in children with asthma, but not to a greater degree than in controls. In fact, basophils and T helper lymphocyte memory transition cells did not increase in children with asthma, whereas they did increase in controls. Even brief exercise in children and adolescents robustly mobilises circulating immune cells.Although it is well recognised that physical activity can influence health in children, the mechanisms that link exercise and health remain enigmatic. Immune responses to exercise could explain some of the adverse (eg bronchoconstriction, urticaria, anaphylaxis1,2,3) or beneficial (reduction of cardiovascular disease risk4,5) health effects of physical activity, and, indeed, growing evidence in children suggests that exercise is associated with a substantial increase in circulating cytokines (such as interleukin 6) and leucocytes.6,7 However, the vast majority of studies to date designed to explore immune and stress responses to exercise in adults and children have used relatively long exercise protocols,8,9 which do not reflect natural patterns of physical activity in children.Real‐life patterns of exercise in children are brief.10 Whether or not short episodes of exercise in children and adolescents cause an increase in circulating inflammatory cells has not been well studied. Consequently, the goal of this study was to test the hypothesis that a standard, brief (6‐min) exercise protocol—used commonly to elicit bronchoconstriction in children—would lead to large increases in circulating inflammatory cells, some of which are associated with specific diseases. As habitual levels of physical activity and related factors, such as body composition and nutritional status, can alter peripheral leucocyte function,11,12 testing this hypothesis would be a necessary first step in understanding the potential mechanistic link between exercise and diseases, such as asthma, in which exercise is a potent trigger of airway inflammation.We chose to measure the levels of the standard circulating leucocytes (ie neutrophils, eosinophils, basophils, lymphocytes and monocytes). In addition, we used flow cytometry to focus on several lymphocyte cell surface markers that have been found, albeit mostly from studies in adults, to have a variety of roles in inflammatory diseases ranging from asthma to atherosclerosis (table 11).). Finally, we elected to study this phenomenon in healthy control children and adolescents, as well as in children and adolescents with a known history of mild‐to‐moderate asthma. Exercise‐induced bronchoconstriction (EIB) is a common and well‐described adverse effect of exercise,13,14 and is related to airway dehydration leading to an abnormal airway inflammatory response.2 Consequently, we hypothesised that the effect of brief exercise on circulating immune cells would be greater than in controls without asthma.Table 1 Cell surface markers evaluatedCell surface marker | Conventional names | Potential role in exercise effects on health |
---|---|---|
CD3+/CD4+ | T helper | Pivotal role in the initiation and perpetuation of the inflammatory response in asthma. Plays a part in formation of atherosclerosis |
CD3+/CD8+ | T cytotoxic/suppressor | CD8+ cells that produce type 2 cytokines have been shown to play a part in asthma inflammation |
CD19+ | B lymphocytes | Production of IgE, important in the allergic mechanism of inflammation. B cells have a protective role in atherosclerosis |
CD3−/CD16+ 56+ | Natural killer | The involvement of NK cells in asthma remains unclear. NK cells have been implicated in the development and progression of atherosclerosis, but their role remains unclear |
CD4+ CD45RA+ | Naive T helper | Naive T helper lymphocytes are essential for responses to new foreign antigens. Adaptive transfer of naive T helper cells accelerates atherosclerosis |
CD4+ CD45RO+ | Memory T helper | Memory T helper lymphocytes migrate towards inflammatory sites and are preferentially activated relative to naive T helper cells after allergen challenge. Most T lymphocytes in atherosclerotic lesions are memory T helper lymphocytes |
CD4+ CD45RO+ RA+ | Transitional T helper cell from naive to memory | Probably represent initial steps in the transition from naive to memory cells |
CD62L+ | L‐selectin | L‐selectin expression on T helper lymphocytes may have a crucial role in bronchospasm. CD62L has been shown to be increased in people with hypertension after stress, and trafficking of lymphocytes to atherosclerotic‐prone aortas is partially CD62L dependent |
CD29+ | Integrin β‐1 subunit | Lower levels of CD29 are found in atopic patients compared with healthy patients |
120.
HB Jatsa ET Ngo Sock LA Tchuem Tchuente P Kamtchouing 《African journal of traditional, complementary, and alternative medicines》2009,6(3):216-221
Clerodendrum umbellatum Poir (Verbenaceae) is traditionally used in Cameroon for the treatment of many diseases including intestinal helminthiasis. This study was undertaken to assess the in vivo antischistosomal activity of its leaves aqueous extract on a Schistosoma mansoni mice model and to determine the most effective dose of this extract. Mice showing a patent infection of S. mansoni were daily treated with C. umbellatum leaves aqueous extract at the doses of 40, 80 or 160 mg/kg body weight for 14 days. Seven days after administration of the extract, schistosomicidal activity was evaluated on the liver and spleen weights, faecal eggs releasing, liver egg count and worm burden. Treatment using C. umbellatum leaves aqueous extract resulted in an important reduction in faecal egg output by 75.49 % and 85.14 % for 80 mg/kg and 160 mg/kg of the extract respectively. These reduction rates did not differ significantly from the 100 % obtained in the group of infected mice treated with 100 mg/kg of praziquantel. C. umbellatum leaves aqueous extract was lethal to S. mansoni worm. A 100 % reduction rate was recorded in the group of infected mice treated with 160 mg/kg of the extract, as well as in praziquantel-treated mice. An amelioration of the hepatosplenomegaly was noticed in both the extract-treated mice and the praziquantel-treated mice. From these results, we can conclude that C. umbellatum leaves aqueous extract demonstrated schistosomicidal properties in S. mansoni model at doses of at least 80 mg/kg body weight. 相似文献